The American Civil Liberties Union is helping three teenage girls fight back against a Pennsylvania prosecutor who has threatened to charge the girls with felony child porn violations over digital photos they took of themselves.

In a federal lawsuit filed Wednesday in Pennsylvania, ACLU lawyers accuse Skumanick (.pdf) of violating the civil rights of three girls. The lawsuit says the threat to prosecute minors for child porn “is unprecedented and stands anti-child-pornography laws on their head.”

The lawsuit comes in the wake of a string of cases around the country in which teens have been arrested on child porn charges for making and distributing nude and semi-nude photos of themselves.

Wired: ACLU Sues Prosecutor Over ‘Sexting’ Child Porn Charges